Physicists discover a new form of light

Physicists from Trinity College Dublin's School of Physics and the CRANN Institute, Trinity College, have discovered a new form of light, which will impact our understanding of the fundamental nature of light.

One of the measurable characteristics of a beam of light is known as angular momentum. Until now, it was thought that in all forms of light the angular momentum would be a multiple of Planck's constant (the physical constant that sets the scale of quantum effects).

Now, recent PhD graduate Kyle Ballantine and Professor Paul Eastham, both from Trinity College Dublin's School of Physics, along with Professor John Donegan from CRANN, have demonstrated a new form of light where the angular momentum of each photon (a particle of visible light) takes only half of this value. This difference, though small, is profound. These results were recently published in the online journal Science Advances.

Commenting on their work, Assistant Professor Paul Eastham said: "We're interested in finding out how we can change the way light behaves, and how that could be useful. What I think is so exciting about this result is that even this fundamental property of light, that physicists have always thought was fixed, can be changed."

Professor John Donegan said: "My research focuses on nanophotonics, which is the study of the behaviour of light on the nanometer scale. A beam of light is characterised by its colour or wavelength and a less familiar quantity known as angular momentum. Angular momentum measures how much something is rotating. For a beam of light, although travelling in a straight line it can also be rotating around its own axis. So when light from the mirror hits your eye in the morning, every photon twists your eye a little, one way or another."

"Our discovery will have real impacts for the study of light waves in areas such as secure optical communications."

Professor Stefano Sanvito, Director of CRANN, said: "The topic of light has always been one of interest to physicists, while also being documented as one of the areas of physics that is best understood. This discovery is a breakthrough for the world of physics and science alike. I am delighted to once again see CRANN and Physics in Trinity producing fundamental scientific research that challenges our understanding of light."

To make this discovery, the team involved used an effect discovered in the same institution almost 200 years before. In the 1830s, mathematician William Rowan Hamilton and physicist Humphrey Lloyd found that, upon passing through certain crystals, a ray of light became a hollow cylinder. The team used this phenomenon to generate beams of light with a screw-like structure.

Analysing these beams within the theory of quantum mechanics they predicted that the angular momentum of the photon would be half-integer, and devised an experiment to test their prediction. Using a specially constructed device they were able to measure the flow of angular momentum in a beam of light. They were also able, for the first time, to measure the variations in this flow caused by quantum effects. The experiments revealed a tiny shift, one-half of Planck's constant, in the angular momentum of each photon.

Theoretical physicists since the 1980s have speculated how quantum mechanics works for particles that are free to move in only two of the three dimensions of space. They discovered that this would enable strange new possibilities, including particles whose quantum numbers were fractions of those expected. This work shows, for the first time, that these speculations can be realised with light.

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Well, in fact this is already known since more than a decade ago. In 2005 it already appeared a paper (from Michael Berry) showing that under this effect (conical diffraction), the propagating light beam carries half optical angular momentum. I'm quite surprised that a journal such as Science Advances that aims to get high impact factor publishes this kind of research..

okay. I was gonna say "That we don't exist", but realized upon "quote"ing the comment i/ts was a link to a joke I found was kinda funny...;-) I gather compose did, too...;-)That said, I suppose after string theory, we'll have to come up with a "dot" theory...

CFD,Your alias reminds me of the old joke about a little indian boy asking his grandfather how parents decided on a child's name. After explaining that the child was named for the first thing a father sees after the child is born.He then questioned the boy - "Why do you ask, Two Dogs Fucking?":-)

Very interesting. This implies that either the SAM or OAM can take on half-integer (that is, fermionic) values for photons, in certain contexts; also, since SAM is subject to uncertainty, this would (in this context, which is two- rather than three-dimensional) imply that photons can behave like fermions, obeying Pauli exclusion and forming aggregates of finite (as opposed to infinitesimal) size. Combining this with 2D materials from materials science, this should be demonstrable on 2D surfaces.

I will be very interested to see where this leads.

This is actually pretty groundbreaking, and I expect that when it starts to catch on, it's going to make some pretty big waves in physics.

The article in Science Advances is open access. Note the "View full text" links in the provided link's body.

SA apparently thinks this is pretty important too. They don't make many articles open access. Congratulations to them for seeing the probable importance of this discovery. This may be the most important discovery in physics I have personally been aware of when it happened in my lifetime.

So? That just means it connects with reality. It's not a final theory and never pretended to be. It's based on experiment. Every step along the way, the SM has been verified, up to and including the Higgs mechanism, the existence of the Goldstone boson, and the Higgs particle itself. You have nothing that can touch it.

and another hundreds are underway (MSSM)...

This is a specious claim immune to evidence and ignorant of the foundations of quantum mechanics, not to mention the results of experiment. I'll take the SM any day over your ethereal speculations.

Sure does. If your speculations won't survive experiment, it's all shizz. Throw it in the garbage and start over. That's what real physicists do. You, on the other hand, try to pretend the experiment never happened. That's philosophy, and sophistry, not physics.

@Whydening Gyre & Da Schneib Personally, I see reason to suspect for the EM that this is a valid result and I do hope the scientists can keep us informed. I have often quoted here on this forum about gamma em converging and producing e+ & e- and I've wondered why/how the g-em 'knows' how to make an e+ & e-. With this article I now wonder if usual forms em, like the neutrino, can change identity and that at certain junctions certain combinations of identities can result in certain point Particles? I know this is a rough generalization but would appreciate your comments. Thanks

CFD,Your alias reminds me of the old joke about a little indian boy asking his grandfather how parents decided on a child's name. After explaining that the child was named for the first thing a father sees after the child is born.He then questioned the boy - "Why do you ask, Two Dogs Fucking?":-)

You beat me to it! lol That's not one you get beaten to the punch on everyday.

I have often quoted here on this forum about gamma em converging and producing e+ & e- and I've wondered why/how the g-em 'knows' how to make an e+ & e-.

It's the amount of energy; if the two photons are energetic enough, they can form muons or even tauons, and it is not limited to leptons; quark pairs can be formed and couple to make mesons (quark-antiquark pair hadrons).

Direct photon-photon interactions are not possible, since photons have no charge. The theory behind these interactions is that one or both of the photons is energetic enough to temporarily form a particle pair that almost instantly annihilate to reform the photon; if, during this brief instant, another photon interacts with one of the pair, or (much more rare) is itself undergoing such a process at the same time as the interaction, then the processes that can happen are governed by the combined energy of the photons.

[contd]Outputs consistent with electron-positron pair interaction with a colliding photon have been observed since 1934; in modern extremely high energy accelerators, a wide variety of particles have been produced, consistent with higher-order lepton and quark pairs interacting either with the other photon or with a pair it has produced.

The particular interaction(s) possible depend upon the energies of the two photons.

In the interaction you're talking about, the photons must be above 1.022 MeV in their combined energy; and in fact, at least one of them must itself be above 1.022 MeV to temporarily form an electron-positron pair. The probing photon then interacts with one of the pair before it can annihilate with its partner, scattering it away.

[contd]Whether this happens or not is a matter of pure chance; if neither photon is energetic enough to form a temporary pair it will not happen at all, and the two photons will not scatter or interact even if they pass through the same point at the same time. They are bosons, and are not prohibited from doing so as fermions are by Pauli exclusion. And even if one photon is energetic enough to form a pair, there is no assurance that it will do so when the other photon is passing through its location.

Thus, this is not a matter of "knowing" that a fermion pair *will* be created; it is a matter of a fermion pair *happening to be* created at just the right time to interact with an impinging photon. Whether it *can* happen depends on there being enough energy in one or both photons to *happen to* create a pair at that moment, and also of it *happening to* do so.

[contd]With that understanding in hand, let's proceed to your question:

With this article I now wonder if usual forms em, like the neutrino,

Neutrinos are not EM. They are leptons, of extremely small (possibly zero, but probably not) mass. Since they cannot be detected except very rarely, it would be extremely difficult to observe such an interaction, and in fact as far as I know it has not been proven to occur due to this difficulty. It is, however, possible; but you must also keep in mind that neutrinos interact only in the weak force (and possibly gravitationally, but that is an open question), so that makes this even more difficult:

[contd]The weak force is weak and slow, and weak charge is not carried by photons, so the only possibility is of two photons, both creating neutrino pairs at the same moment that they are coincident, and the two neutrino pairs happening to interact in the weak force in the extremely limited time available, both of which are extremely improbable making this an enormously extremely improbable event which is almost impossible to detect in the first place. This is why there are no experimental reports of it. It is very nearly impossible, piling all these extreme improbabilities atop one another.

...can change identity and that at certain junctions certain combinations of identities can result in certain point Particles? I know this is a rough generalization but would appreciate your comments.

Well, photon-photon interactions are possible, as I have outlined above, but they conserve all quantities and there is no need for them in order to explain the results above, in the article we are commenting on.

You also should not use "result in certain point Particles" in this context; the photons are also point particles. What you mean is whether bosons of sufficient energy can form temporary fermion pairs, and whether members of those pairs can then interact with other particles, and this can happen, but the pairs are always a particle and its antiparticle, in order to obey all the conservation laws, and if they do not happen to interact with another particle, they will recombine to form the original gamma photon.

@Whydening Gyre & Da Schneib ... I know this is a rough generalization but would appreciate your comments. Thanks

MM,I am flattered you would include me in your request. However, Da Schneib is eminently more informed than I on these matters...:-)And I noticed, he has prepared a pretty complete (and lengthy...) series of technical comments for you, that I would not have even come close to presenting. (I followed along for a while, but then my ADHD kicked in...) Mine would be more a visual of an artsy fluidic nature without the esoteric jargon to back it up.So, in summation - Yeah, what HE said...

[qWith this article I now wonder if usual forms em, like the neutrino, can change identity They DO change identity as they pass thru matter - nuetrino "flavoring", remember? (Was in an article a month or so back, bout changes as they left the sun)

and that at certain junctions certain combinations of identities can result in certain point Particles?

You would think so. Specially considering that their density would probably be higher in matter dominated localities. (More "flavors" interacting)

I know this is a rough generalization but would appreciate your comments. Thanks

@Da Schneib & Whydening Gyre. Da Schneib many thanks for your comments, most appreciated. I understand. The points where I err, again thanks. However I am aware of say 75% of what you posted but my problem is using correct terminology in a brief post. Where I say '...knows...' I later realized that this does sound like the EPR 'hidden variables' v entanglement. What I meant to suggest was the 'entanglement' point of view. I have assumed that although the article is about '..a new form...' that the new form would still be subject to entanglement theory(ies). I do appreciate that high energies or particular energy limits probably define what happens with/in/after interactions but my question is 'why'. I don't 'intuitively' feel satisfied by energy limits being the whole answer. I'll try to explain that feeling as best I can but you will have fill in the gaps and then correct me as you see fit (Ha!). (cont.)

I 'intuitively' feel that 'orientation' is a factor too. That is to say, there is point where, say, '1/2' is important before the the full '1' result occurs and it is the former which decides the outcome. I'm rather saying that there might be a qaternion function, different for each of the 3D, that might need to be applied before spinor considerations. I'm suggesting that the quaternion function represents the '1/2' and spinor, '1'. This is a very loose analogy to my 'intuitive' problem because I've left out an important factor, Time. I'm also wondering if the various combinations of the 'quaternion functions' are also involved where some might be 'allowed' and others not.I've tried to give my 'intuition' a math feel and you might be be able to come up with something more appropriate. Thanks in advance.@Whydening Gyre Ha!, understood but thanks for your time anyway.To both, have a good day.

@Mimath The first most important thing to understand is that entanglement isn't really important in photon-photon interactions. The only place it enters in is the fact that the photon(s) must form pairs that are entangled; once one of the pair interacts with another particle, they are no longer entangled. The entanglement is decohered by that interaction, and in an unpredictable manner since more than one parameter may interact: position, momentum, and both OAM and SAM may be affected. That's why photon-photon interactions have little to do with the experiment we are discussing here.

I'll look at other points in your two posts shortly; right now I'm kinda burnt out from various RL phenomena.

@Whydening Gyre Ha!, understood but thanks for your time anyway.To both, have a good day.

MM,Einstein once said the only valuable thing is intuition.There is something about spin and orientation that I feel is important, too. I lay awake at night (after scouring these conversations) trying to visualize the symmetry of it - in 3d.Thanks for the input on your intuition. It's provided me some additional "variables" and controls, to add in to my visualizations.I know, I know... Too Garrett Lissi-ish....:-)

@Da Schneib Thanks, and understood. @Whydening Gyre and didn't someone say that if you can visualize what the math say you are one step closer to enlightenment, or something like that anyway...why not try it when surfing (Ha!). Actually, I simplified my analogy because of trying to maintain a 3D stance and it so easy to fall into a 4,6D etc trap where things for my limited knowledge get messy. I'm not sure whether they would be relevant here anyway.

I do appreciate that high energies or particular energy limits probably define what happens with/in/after interactions but my question is 'why'. I don't 'intuitively' feel satisfied by energy limits being the whole answer. ... I 'intuitively' feel that 'orientation' is a factor too.

You go on to discuss, I think only as an analogy, quaternions and spinors. Then you introduce time as a factor, implying that the development of these quaternion and spinor functions over time determines what products emerge from these photon-photon interactions.

I think what's going on here is that you're wondering if there could be some other factor that somehow determines what happens in photon-photon interactions.

[contd]I doubt this, just as I doubt that there is any particular factor other than blind chance that determines when a neutron chooses to decay; such factors have been looked for since we first discovered radioactivity and determined that decay is a random event. This isn't just us throwing up our hands and saying "It's random," detailed statistical analysis supports this determination. And the same is true of other decays, including those of both heavy quarks to lighter ones down to the lightest up quark combination, two ups and a down forming a proton, and the same for the leptons, with the heavier ones decaying in a chain ending with neutrinos and electrons. These decays, and their probabilities, are fairly well characterized in the CKM and PMNS matrices for quarks and leptons, respectively.

[contd]The probabilities in photon-photon interactions are controlled by just such random chances; that is, how often photons experience pair production and subsequent annihilation back to the original photon as they propagate. This is further influenced by the energy of the photons, which governs what pairs it is possible for them to form. A photon below 1.022 MeV is incapable of forming any pair at all since its energy is insufficient to form two electrons, the lightest particles we know of. As we increase the energy of the photons, we pass thresholds where it becomes successively possible to form quark pairs, muon pairs, and so forth. However, it is not certain that above these thresholds if a pair is produced it will only be these newly allowed particles; lighter pairs may be formed as well, and the distribution is still random among which possible pair will be produced in a given interaction.

[contd]Topping all of this off is the fact (again shown by statistics) that when a Heisenberg-conjugate parameter is determined, its complementary parameter gets a random value. To demonstrate this, think of the three-polarizers experiment: after the second polarizer, the values of the spins on the original axis measured in the first polarizer, and about to be measured again in the third, is random; in the original form, with the polarizers oriented 0-π/4-0 (or if you prefer, 0°-45°-0°), you get a 50%-50% probability distribution at the third polarizer. This is very strong evidence of true randomization.

I don't think that spin state (or your postulated quanternion-like or spinor-like parameter) has anything to do with what particles are produced; assuming there is any relevance at all, I would expect it to affect the momenta of the particles produced, not their nature.

Actually, I simplified my analogy because of trying to maintain a 3D stance and it so easy to fall into a 4,6D etc trap where things for my limited knowledge get messy. I'm not sure whether they would be relevant here anyway.

This is actually interesting because there are fundamental characteristics of spaces that depend upon their dimensionality.

For example, in spaces of odd dimensionality, the thing we call "axes of rotation" point in directions that are defined in the space; but in spaces of even dimensionality they need not and at least some of them do not. The trivial example is a space of dimension two: in this space, rotations in the only available direction, the x-y plane, have an axis that points in the z direction, which does not exist in the 2D space.

[contd]In SRT in 4D spacetime, we find that three of the six axes of rotation point in such directions: the x-t, y-t, and z-t planes have axes that point in directions that do not exist in the 4D manifold; but the x-y, x-z, and y-z planes all have axes that point, respectively, in the z, y, and x directions, as they do in the 3D space of Galilean-Newtonian physics.

1. How dark is the night sky in 1/2ħ photons? Could E/T be talking on this ultra quiet band. (What does the sun look like?)

Since we haven't looked anything I said here would be speculation; keep in mind also that since these can only be defined on a 2D manifold, they wouldn't be available free parameters on a photon propagating in 3D space and coming from ET out there somewhere.

While understanding the difference between photons and static fundamental particles,

Be very careful here. Photons are fundamental particles too just as W and Z and gluons (and hypothetically, gravitons) are. The fact they are bosons doesn't make them other than fundamental particles in quantum physics. And this is highlighted by the W and Z particles which have mass and cannot move at the speed of light.

one can still call on analogs, indeed mathematical analogs, "Is the electron a photon with toroidal topology? ", J.G. Williamson et al., Annales de la Fondation Louis de Broglie, Volume 22, no.2, 133 (1997) , and argue (perhaps, poorly) that confined quarks, are not entirely within Minkowski space, and could be affected by higher space/time (10d string?) physics as the material.

I'll have to have a careful look at this; I have seen this argued elsewhere in much less sophisticated terms. Hopefully there is a version of this paper available on arXiv.

My initial reaction is, no, but that's certainly not definitive; let me look at the paper and reactions to it and I might have something more to say.

For a pretty good answer, see Loren Petrich's answers on the matter; I have talked with Loren before this, and he knows this stuff in detail. The objections he raises are in post #13 on the thread I will link on the Physics Forum, and I see no refutation of them, and I'm fairly convinced by his arguments.

BTW, this is the same paper I've seen linked elsewhere. As Loren says, it's not enough to duplicate part of the experimental results, for a coherent and consistent theoretical result one must duplicate all of them, and trivially, this hypothesis does not duplicate electron results above 100GeV that have been well known for a long time.

@Da Schneib many thanks and I appreciate it you taking time to comment. You argue logically so it's that much easier for me (dummy layman Ha!) to get the gist. However, I still feel there is a rotational/transformation going on at the perhaps quark/gluon level but at the moment I can't 'off the top of head' explain it to you in a way that would allow you agree/deny/or falsify my 'idea'. I'm not satisfied with saying 'I think this and that' without giving some arguable foundation so I hope you'll bear with me a little more while I spend a day trying to formulate where I'm going. (Hope you've recovered from the RL phenomena. Actually I have an amusing story my study of RC & RL circuits (long time ago now). Perhaps I'll send it to you privately as I'm sure it will give you a laugh.)

Sorry, guy, they apparently are now randomly deleting comments for no particular reason. I'll try and see if I can remember it and post later.

I also gave you a 5 for a good question; that also seems to have disappeared. Here it is back again in the meanwhile.

Hey @physorg, get your act together. You're blowin' it. If you need someone to help fix your site and figure out why you keep losing stuff I might be talked into it over the weekend, but be prepared to pay for my time.

Sorry, guy, they apparently are now randomly deleting comments for no particular reason. I'll try and see if I can remember it and post later.

I also gave you a 5 for a good question; that also seems to have disappeared. Here it is back again in the meanwhile.

Hey @physorg, get your act together. You're blowin' it. If you need someone to help fix your site and figure out why you keep losing stuff I might be talked into it over the weekend, but be prepared to pay for my time.

@Da Schneib many thanks and I appreciate it you taking time to comment. .... However, I still feel there is a rotational/transformation going on at the perhaps quark/gluon level but at the moment I can't 'off the top of head' explain it to you

MM, apologies for Intrusion in converse with DS. I agree on the rotation aspect of your "intuition". I had a pretty decent visual after your input last nite. Something bout 2 different direction spins (1/2 and 1/3) and... maintenance of orthogonality..(?)

I'm not satisfied with saying 'I think this and that' without giving some arguable foundation so I hope you'll bear with me a little more while I spend a day trying to formulate where I'm going.

You are way ahead of me on the "formulation" aspect, I suspect, so let me know, too...:-)

@Whydening Gyre 'You are way ahead of me on the "formulation" aspect, I suspect,...' I doubt that very much I'm just an average sort of guy with many interests. However, I'll try to put a human physical condition in a kind 'wallop' orientation (qm charge???). A martial artist prepares for a spin kick (of which there are many types) but in this case a straight forward circular kick striking a target with the ball (or heel) of the foot. The angular momentum is the total force applied to the target while the MA is basically a rotating vector. However, in addition there is the next stage up. Not only relying on the basic, AM can be given extra M by curving the foot via the knee just before impact so that it springs back towards the center of rotation. Depending on other factors the impact force could be increased by as much as 50%, or if you like 1/2+1/2 = 1 (the downward method might 1/3+1/3+1/3 =1). I'm sure you can see where I'm going with this.On the QM level..(cont)

(cont.) such ideas might be analogous to why OAM and SAM. Other more complicated kick variations (jumping at the same time etc.) might even be analogous to say, magnetic moment and so on. One of my tech college teachers always use to say '....that Nature has already given various forms which display the answers we seek., we only have to look..'. The EM fine structure constant of 1/137 for example might have a connection to the Golden Ratio and approximations to the golden ratio have been shown in various ways. That is not to say they aren't complicated, for QM is already that just considering size alone but sometimes I wonder if we do things 'up here' as a kind image of of what goes on 'down there'.

... A martial artist prepares for a spin kick (of which there are many types) but in this case a straight forward circular kick striking a target with the ball (or heel) of the foot. The angular momentum is the total force applied to the target while the MA is basically a rotating vector. However, in addition there is the next stage up. Not only relying on the basic, AM can be given extra M by curving the foot via the knee just before impact so that it springs back towards the center of rotation. Depending on other factors the impact force could be increased by as much as 50%, or if you like 1/2+1/2 = 1 (the downward method might 1/3+1/3+1/3 =1). I'm sure you can see where I'm going with this.On the QM level..(cont)

@Whydening Gyre 'Fractalization of a sort...BE the quantum, Grasshopper...:-)...BTW - Did MA and was gymnast as a youth. At 62 - not so much...:-)'Ha! yeah, right on. I was a track athlete in my younger years (sprint), Shot, Javelin and the like. At 73 still teaching MA.' Looking forward to your more defined explanation to DS.' This is proving difficult because other events have taken over at present but will definitely do it at some point. It's important that I get it right so that DS is not confused. i.e. spent yesterday evening trying to using vector scalar & cross product as the base for a quaternion explanation of my thoughts (first real terms = 0) but now, I'm not quite sure if that's the appropriate route. Perhaps using q =1 so that sine and cosine might be best. Ha! by the time I finish, this thread will probably be closed...(@Da Schneib maybe send you a private message...is that okay?)

Spendin' a lot of CPU cycles on database stuff just ATM, and quaternions aren't exactly my strong suit. But if I get time, I'll see what I can do. Yes, you may send me a PM if you know how, but I'm not going to share any contact details here.

@Da Schneib It was not my intention for you to concern yourself about quaternions. It's just that I am using q for something completely different but wondered if I could use them in present context. In fact, I'm already trying to form an 'intuitive' representation so that I don't have to write obscure formulas yet at the same time give you a more accurate view of my thoughts. I think what is more important is to keep space-time AND space & time on a kind of mobius strip...separate yet not so, if you see what I mean Ha! Please Disregard the personal message because if I too late here I'll probably 'catch' you on another thread sometime.

@Da Schneib I have rushed this a bit but I don't want to keep it hanging around otherwise my 'intuition' will become boring Ha! Also I wanted to to keep the analogy on topic. Looking at the notes I written what it really boils down to is giving EM another degree of freedom but at the same time trying to remain within space-time 4D. In addition to this I've assumed the Time between quantum entities and their interactions is relative to the entities.Let's say the photon direction is x (horizontal) so SAM in the (y(vertical),z) plane interacts with a spiral phase material (excuse my lack of correct terminology) so that a helical beam with OAM is produced. The extra degree of freedom might be in the (x,y) plane so as maintain the direction. I thinking that this would produce a kind of 'tumble' effect. I am not suggesting a full 'tumble', but a fractional one might just offset OAM & SAM enough to produce effects detectable by improved techniques. I have ignored the (x,z) plane...cont

cont...because I think a 'tumble' in that plane would be in a different direction to the photon direction. My own objection here would be that velocity might be less than c (as when passing through different mediums) or that the 'tumble' would have to part of the phase group undulations necessarily >c.Layman's rubbish eh? Ha!

Electro-magnetic waves do not exist at "less than c", a violation of the Mass/Energy Equivalence Principle of Special Relativity better known as: E=mc².

Measurements of c in high gravitational fields is better calculated taking into account the Shapiro Effect by the following equation:

Deflection= GMK/c²ln(R)........ as opposed to 4GM/c²R

Observations of apparent significant deflection suggests that the deflection of light by massive objects can be significant, no proofs have been shown that deflection actually slows photon velocity but only that there is resulting increased trajectory of the flight-path resulting in bent photons producing an observed lagging effect of time due to the angle of observation, thus the curvature of deflected (gravitationally lensed) starlight has a longer flight-path compared to non-deflected starlight from the same distance of the source to the observer.

@Benni 'Electro-magnetic waves do not exist at "less than c", a violation of the Mass/Energy Equivalence Principle of Special Relativity better known as: E=mc². '

Read my brackets too '(as when passing through different mediums)' DEFRACTION, the index water 1.33, diamond 2.42, That is, index =c/(v medium).The rest of your post talks about SR/GR and the topic here is at quantum level. So you are off topic too.

In precisely what context please ?(also heard this from those who can't do Math :/)

Although its true re special relativity a photon instantly connects one orbital/energy state change to another since time is not relevant for a photon ie Null geodesic etc..

I do see you haven't seen the evidence directly (blind ?) or haven't made the math/physics connection re the functioning of the most pertinent example indirectly (not blind ?) & leapt off into nether regions not connected practically with cause/effect extremely well described by Math & the immense consistency within Physics ?

There are many you tube videos (& great sound btw) that covers the issue of quantum mechanics very well indeed - from introductions, equivalent integer like concepts to complex vector fields etc.

I highly recommend you at least listen to them, even without the benefit of photons ;-)

There are lifetimes (and photon band widths) associated with transitions. There is no such thing as an instantaneous transition

Um No, it IS correct *from* inertial reference frame (IRF) issue as I did mention Special Relativity & Null Geodesic...

ie To fully appreciate it needs to be from the photon's IRF - time is; non-existent, irrelevant, meaningless or our interpretation re its basis isn't yet understood, relevant math:-https://en.wikipe...lativity

Tangentially similar to conundrum observed as electron "moves" between orbitals re photon emission/absorption - it effectively traverses space instantly, its maybe a spooky aspect which also has math to describe it & somewhat related to:-https://en.wikipe...ary_time

Also like the wider view of the phenomenological aspects of the conundrum re Pauli's exclusion principle in respect of electrons - implying there's only one in the whole universe ;-)

Note, I did refer to photon from *its* IRF, are you saying Special Relativity (SR) as applied to the photon & Null Geodesic (NG) not relevant in respect of my post responding to HyperFuzzy & the link for audience's consideration ?

ie. Where was I wrong re the 2 sentences relevant to the issue in my last post & especially in reference to SR & NG ?

Are you saying its not applicable or it is, can you articulate please ?

Will I be first in predicting the existence of other forms of light where the angular momentum will be fractional values of Planck's constant, 1/4, 1/8 etc?While you consider that, consider this:is.gd/impotenceofchance

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